For your situation, I would suggest jumping straight to V90 cards if youre planning on shooting 4K All-I. Honestly, Ive been shooting with the RF system since it launched and I’ve learned the hard way that cutting corners on media is just asking for a ruined shoot. While the R6 Mark II is amazing, that All-I bitrate is basically right at the limit of what V60 can handle—its risky business tbh. Here's what I recommend based on years of testing: 1. For absolute reliability, get the Sony SF-G Series TOUGH UHS-II 128GB V90. They’re literally built like tanks and I havent had one fail yet. Plus, no plastic ribs to break off in the slot.
2. If you want a better price-to-performance ratio, go with ProGrade Digital SDXC UHS-II Video Speed Class 90 (V90) 256GB. These are my daily drivers and they handle heat way better than the SanDisks in my experience.
3. If you ever switch to IPB (Long GOP) to save space, the SanDisk Extreme PRO SDXC UHS-II Card 128GB V60 is a solid middle ground, but it might struggle with the All-I peaks. I would suggest avoiding the cheap "no-name" V90 cards you see on Amazon... they might work for a week and then just die. Also, make sure to format the card in-camera every time you start a new project. It helps keep the file system clean and reduces those buffer errors. Good luck with the R6 II—it's a beast! peace

After years of shooting, I've found ProGrade Digital 256GB SDXC UHS-II V60 cards handle 470Mbps All-I bitrates fine. V90 is usually safer, but these are the best middle ground for value, honestly.

yo! Congrats on the R6 II upgrade, literally such a beast of a camera right?? I actually had a similar nightmare when I first started shooting video on my mirrorless. I thought my old cards were fine but then i was filming a wedding and the camera just... stopped. It was so embarrassing lol. Quick question before I dive into the deep end tho - how long are your typical recording sessions? Like, are you doing 30-minute interviews or just short b-roll clips? That really changes how much you need to spend on capacity vs speed. Honestly, if you wanna save cash but still hit those All-I bitrates without the V90 price tag, I've had realy good luck with the Lexar Professional 1667x 256GB SDXC UHS-II V60 cards. They’re super affordable compared to the Sony ones and I havent had one fail yet. But if you’re highkey worried about the 4K 60fps All-I (which is like 470Mbps), you might wanna look at the Kingston Canvas React Plus 256GB SDXC UHS-II V90. It’s usually way cheaper than SanDisk but gives you that V90 peace of mind. Basically, the "trap" is buying from random third-party sellers cuz fakes are everywhere and they run way hotter. I always buy from verified shops now... just not worth the risk imo. Hope that helps! peace 👍

> Specifically, I'm looking for something that can reliably handle 4K All-I recording without breaking a sweat. Totally get the frustration lol, that 'recording stopped' message is basically a jump scare at this point. If you look at the current market data and sustained write benchmarks, there's actually a huge gap between 'peak speed' and 'sustained speed' that a lot of brands hide. While everyone goes for SanDisk, they've been a bit inconsistent lately with their QC and tend to run quite hot in mirrorless slots. If you want the best price-to-performance ratio right now, I’d look at the Angelbird AV PRO SD MK2 V60. Angelbird is huge in the cinema world because they prioritize consistent data streams over flashy burst numbers. They handle All-I perfectly and are built to deal with the thermal demands of high-bitrate video. Another solid market alternative is the Sabrent Rocket V60 SD UHS-II Card. Sabrent is relatively new to the SD space but they use high-quality flash controllers that run way cooler than the legacy brands. You technically don't need V90 for the R6 II's 470Mbps All-I bitrate—which is roughly 58.75 MB/s—so a high-quality V60 that actually holds its speed is the real sweet spot tbh.

Yeah, the point about sustained write speeds versus those flashy peak numbers on the box is spot on. Honestly, most people just look at the sticker and call it a day, but that is exactly how you end up with dropped frames in the middle of a shoot. I agree that heat management is the real silent killer here, especially in these compact RF bodies. Not sure if this is still a major factor with the R6 II, but I think I recall hearing that the way the camera handles the buffer write-out can be a bit aggressive if the card is even slightly fragmented. One thing I always tell people to do before dropping big bucks on new media is a deep low-level format on their PC rather than just doing the quick format in-camera. It sometimes helps reset the controller logic on the card, though I am not 100 percent sure if that actually fixes the thermal throttling issue or just masks it for a while. If you are the technical type, you might want to try:

• Running a sustained write test like AJA System Test on your current cards
• Checking the card contacts for any residue that could increase resistance
• Seeing if the error happens more often when the battery is low IIRC, some DIYers were looking into external cooling for the card door area, but that is probably overkill for most. Just something to keep in mind tho.

Ngl I'm in the exact same boat right now with my R6 Mark II and it's driving me crazy. That recording stopped message is basically my arch nemesis at this point. I've been digging into the raw data sheets for days trying to figure out which card actually maintains its minimum write speed under load because I hate the idea of losing footage. I've been trying to choose between the Sony TOUGH-G series SDXC UHS-II V90 and the Wise Advanced SDXC UHS-II V90. The Sony is built like a tank which is cool for my DIY setup, but the Wise cards actually show really impressive sustained performance in the technical benchmarks I've seen. I also looked at the SanDisk Extreme Pro UHS-II V90 128GB but I'm worried about the quality control and heat issues some people mentioned. Honestly I still can't decide because the specs are so close but the real-world reliability is what matters. I'm just as stuck as you are tbh... I'm almost tempted to just buy a few and run my own stress tests with a card reader to see which one throttles first.